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Understanding and controlling polymorphism in molecular solids is a major unsolved problem in crystal engineering. While the ability to calculate accurate lattice energies with atomistic modelling provides valuable insight into the associated energy scales, existing methods cannot connect energy differences to the delicate balances of intra- and intermolecular forces that ultimately determine polymorph stability ordering. We report herein a protocol for applying Quantum Chemical Topology (QCT) to study the key intra- and intermolecular interactions in molecular solids, which we use to compare the three known polymorphs of succinic acid including the recently-discovered γ form. QCT provides a rigorous partitioning of the total energy into contributions associated with topological atoms, and a quantitative and chemically intuitive description of the intra- and intermolecular interactions. The newly-proposed Relative Energy Gradient (REG) method ranks atomistic energy terms (steric, electrostatic and exchange) by their importance in constructing the total energy profile for a chemical process. We find that the conformation of the succinic acid molecule is governed by a balance of large and opposing electrostatic interactions, while the H-bond dimerisation is governed by a combination of electrostatics and sterics. In the solids, an atomistic energy balance emerges that governs the contraction, towards the equilibrium geometry, of a molecular cluster representing the bulk crystal. The protocol we put forward is as general as the capabilities of the underlying quantum-mechanical model and it can provide novel perspectives on polymorphism in a wide range of chemical systems.
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Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a central neurodegenerative disease due to mutations in the tubulin beta-4A (TUBB4A) gene, characterized by motor development delay, abnormal movements, ataxia, spasticity, dysarthria, and cognitive deficits. Diagnosis is made by integrating clinical data and radiological signs. Differences in MRIs have been reported in patients that carry the same mutation; however, a quantitative study has not been performed so far. Our study aimed to provide a longitudinal analysis of the changes in the cerebellum (Cb), corpus callosum (CC), ventricular system, and striatum in a patient suffering from H-ABC and in the taiep rat. We correlated the MRI signs of the patient with the results of immunofluorescence, gait analysis, segmentation of cerebellum, CC, and ventricular system, performed in the taiep rat. We found that cerebellar and callosal changes, suggesting a potential hypomyelination, worsened with age, in concomitance with the emergence of ataxic gait. We also observed a progressive lateral ventriculomegaly in both patient and taiep, possibly secondary to the atrophy of the white matter. These white matter changes are progressive and can be involved in the clinical deterioration. Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) gives rise to a spectrum of clinical signs whose pathophysiology still needs to be understood.
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This contribution explores the bifunctional catalytic activity of water clusters ((H2O)n with n = 1-5) in organic chemistry similar to that observed in the formation of H2SO4 in acid rain (Chem. Commun., 53, 3516, (2017)). We considered for this purpose the Hydrolysis of Epoxides (HE), in particular, that of oxirane and its methyl derivatives. Surrounding water molecules with H-bond cooperative effects decrease the activation energy of the rate-limiting step of HE in condensed phase, especially when they lead to an anti-periplanar attack on the alkoxide leaving group. Furthermore, the water molecules have a bifunctional catalytic role in HE by (i) increasing the nucleophilic and electrophilic character of the attacking oxygen atom and the leaving group of the reaction, respectively, and (ii) placing the reactants in a suitable disposition for the substitution to occur. Overall, this investigation provides relevant insights into the collective action of water molecules on organic reactions in neutral, basic and acid media.
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Hypomyelination with atrophy of the basal ganglia and cerebellum (H-ABC) is a neurodegenerative disease due to mutations in TUBB4A. Patients suffer from extrapyramidal movements, spasticity, ataxia, and cognitive deficits. Magnetic resonance imaging features are hypomyelination and atrophy of the striatum and cerebellum. A correlation between the mutations and their cellular, tissue and organic effects is largely missing. The effects of these mutations on sensory functions have not been described so far. We have previously reported a rat carrying a TUBB4A (A302T) mutation and sharing most of the clinical and radiological signs with H-ABC patients. Here, for the first time, we did a comparative study of the hearing function in an H-ABC patient and in this mutant model. By analyzing hearing function, we found that there are no significant differences in the auditory brainstem response (ABR) thresholds between mutant rats and WT controls. Nevertheless, ABRs show longer latencies in central waves (II-IV) that in some cases disappear when compared to WT. The patient also shows abnormal AEPs presenting only Waves I and II. Distortion product of otoacoustic emissions and immunohistochemistry in the rat show that the peripheral hearing function and morphology of the organ of Corti are normal. We conclude that the tubulin mutation severely impairs the central hearing pathway most probably by progressive central white matter degeneration. Hearing function might be affected in a significant fraction of patients with H-ABC; therefore, screening for auditory function should be done on patients with tubulinopathies to evaluate hearing support therapies.
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Discapacidades del Desarrollo/genética , Trastornos Distónicos/genética , Pérdida Auditiva Sensorineural/genética , Tubulina (Proteína)/deficiencia , Sustitución de Aminoácidos , Animales , Percepción Auditiva , Preescolar , Núcleo Coclear/patología , Enfermedades Desmielinizantes/genética , Modelos Animales de Enfermedad , Oído Interno/fisiopatología , Potenciales Evocados Auditivos , Femenino , Pérdida Auditiva Sensorineural/fisiopatología , Humanos , Colículos Inferiores/patología , Masculino , Mutación Missense , Vaina de Mielina/patología , Mutación Puntual , Ratas , Ratas Mutantes , Ratas Sprague-Dawley , Tubulina (Proteína)/genéticaRESUMEN
High resolution fluorescence microscopy requires optimization of the protocols for biological sample preparation. The optical and chemical characteristics of mounting media are among the things that could be modified to achieve optimal image formation. In our search for chemical substances that could perform as mounting media, 3,3'-thiodipropanol (TDP) emerged as a sulfide with potentially interesting characteristics. In this work, several tests of its performance as a mounting medium for fluorescence microscopy of biological samples were performed, including the labeling of filamentous actin with fluorescent phalloidins. The refractive index dispersion curve of pH-adjusted TDP was experimentally obtained in the visible range and compared to the dispersion curves of commercial and lab-made mounting media. The effects on the fluorescence of commonly used dyes were tested by using TDP as a solvent and measuring the relative fluorescence quantum yield of the dyes. By being able to mix TDP in any concentration with water and 2,2'-thiodiethanol (TDE), it was possible not only to fine-tune the refractive index of the resulting solution, but also to preserve the compatibility of TDP with the most popular and efficient fluorescent actin staining used in biological microscopy.
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RESUMEN Introducción: actualmente, el Accidente Cerebrovascular (ACV) produce importantes limitaciones, discapacidades y constituye una de las primeras causas de muerte a nivel mundial. La mortalidad hospitalaria es uno de los indicadores más utilizados para medir la calidad de la atención en los servicios de salud. Objetivo: determinar la tendencia de la mortalidad por ACV. Métodos: se realizó una investigación descriptiva de una serie de casos. El universo fueron 382 pacientes; el total de fallecidos con el diagnóstico clínico, tomográfico y/o necrológico de ACV, del 2012 hasta el 2017, en el Hospital Clínico-Quirúrgico Lucía Íñiguez Landín. Los datos recogidos fueron procesados estadísticamente. Resultados: en los años estudiados fallecieron por ACV, un promedio anual de 63 pacientes. El grupo etario de 71 a 80 años sobresalió con un promedio de 17,5 fallecidos. Llamó la atención la tendencia al aumento del grupo de 51 a 60 años. Predominó el sexo masculino con un promedio de 35,6 fallecidos; aunque la tendencia fue a igualarse. Prevalecieron las hemorragias intracerebrales con 34 fallecidos como promedio, y la hipertensión arterial acompañó a más del 50% de los fallecidos, en la mayoría de los años estudiados. Las causas directas de los fallecimientos fueron: el edema cerebral y la hipertensión endocraneana refractaria, principalmente durante las estadías hospitalarias cortas o intermedias. Conclusiones: la mortalidad por ACV tuvo un comportamiento similar en los diferentes años; pero con una tendencia a elevarse con el tiempo y aparecer en edades más tempranas.
ABSTRACT Introduction: nowadays, Cerebrovascular Accident (CVA) invalidantes patients and is one of the main mortality causes around the world. Hospital mortality is one of the most adequate indicators to measure the attention quality, in health services. Objective: to determine mortality tendency of CVA. Methods: a descriptive series of cases research, with the universe of the 382 deceased patients, diagnosed with tomographic and/or obituary of CVA, from 2012 to 2017, at the Clinical Surgical Hospital "Lucía Íñiguez Landín". Data were processed statistically. Results: during the years of study, an average of 62 patients perished for CVA. Age bracket from 71 to 80 stood out with 17.5 average. Tendency raised in the group from 51 to 60. Males prevailed with a mortality of 35.6 average; though it tend to become equal. Intracerebral Hemorrhages prevailed with a 34 average mortality, and arterial hypertension accompanied the 50% of dead patients, in most of the studied years. Mortality direct causes were the cerebral edema and intracraneal hypertension with refration, mainly when hospital stays were short or intermediates. Conclusions: CVA mortality behaved differently through the studied years; though it increased and appeared, more frequently, in premature ages.
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A noninvasive, quick, reliable, and relatively cheap procedure for the diagnosis of onychomycosis is put forward. It is known that a nail may show an abnormal appearance, although only 50% of all the nails having such an appearance may owe it to the presence of onychomycosis; hence, adequate diagnosis of nail disease is needed for appropriate prescription of medication and treatment of the nail. In order to contribute to the process of improvement in the diagnosis, a procedure based on the analysis of medium-range infrared images is presented in which it is possible to observe energy changes mostly due to the changes in emissivity of the nail. As a nail is more affected by onychomycosis, such changes become more intense. Also, it was found that a nail without onychomycosis has a lower temperature than toe skin, but has a higher emission of energy. Fifty percent of the ailments that may a cause a fingernail or toenail to have an abnormal appearance are not considered in the present work.
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Procesamiento de Imagen Asistido por Computador/métodos , Uñas/fisiopatología , Onicomicosis/diagnóstico , Termografía/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Onicomicosis/fisiopatología , Fenómenos Fisiológicos de la Piel , Dedos del Pie/fisiopatologíaRESUMEN
Aunque se asume que la educación sanitaria mejora los estilos de vida de los pacientes hipertensos, no existe suficiente bibliografía que apoye esta asociación. Objetivo: Evaluar el efecto de la educación sanitaria ofrecida a los pacientes hipertensos sobre sus prácticas de ingesta de sal y ejercicio físico. Material y métodos: Estudio descriptivo, transversal y basado en encuestas aplicadas a 179 pacientes hipertensos que acudieron entre junio y julio de 2009 a los servicios de medicina general, medicina interna y cardiología independientemente del motivo de atención. Se analizó con el programa SPSS versión 17.0 y aplicando el test de chi cuadrado. Resultados: El 67% fue del sexo femenino, 60,9% era mayor de 60 años y el 72,1% tenía educación secundaria o superior. El 25% había recibido charlas y 22% material educativo en salud en los últimos 6 meses. No se encontró asociación significativa entre haber recibido educación sanitaria con la práctica de actividad física regular ni de menor ingesta de sal. Conclusiones: En este estudio, la educación sanitaria no tuvo influencia sobre la práctica de ejercicio físico ni sobre la ingesta de sal.
Although it is assumed that health care education improves life style in hypertensive patients, there is no enough evidence to support its implementation. Objective: Evaluate the effect of health care education on salt ingestion and physical exercise in hypertensive patients. Methods: Descriptive, cross-sectional study based on surveys applied to 179 hypertensive patients who attended the internal medicine and cardiology outpatient clinics from June to July 2009. Chi square test was performed using the SPSS statistical package version 17.0. Results: 67% were females; 69% were older than 60 years of age; 72.1% had secondary school level or superior education level. Health care education was received by 25% of the participants, 22% had received printed material in the last 6 months. Having received health care education was not associated with less salt ingestion or with more physical exercise. Conclusions: Health care education did not influence salt ingestion and physical exercise in this study.
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Humanos , Masculino , Adulto , Femenino , Persona de Mediana Edad , Atención a la Salud , Cloruro de Sodio , Educación en Salud , Ejercicio Físico , Hipertensión , Pacientes , Epidemiología Descriptiva , Estudios TransversalesRESUMEN
En la atención primaria lidiamos con variados problemas de salud con diverso impacto en el individuo y su familia. Asimismo, circunstancias previsibles en la vida del individuo y su familia requieren atenuar el impacto de un evento crítico para su desarrollo. Existen 5 cinco niveles de intervención familiar basados en el grado de involucramiento familiar bajo la premisa de que ello posibilitaría una mejor comprensión del problema del individuo y por tanto, mayores posibilidades de resolverlo. Es importante, además, diferenciar cuando un problema familiar requiere derivación a otro nivel de intervención. En nuestro país requerimos adecuar los servicios, formar profesionales con habilidades específicas para trabajar con familias y reforzar las normas que posibiliten el avance en este campo.
We face different health problems in primary care, and they have variable impact in both individuals and their families. Also, some foreseeable circumstances in the lives of the individual and of his/her family are required in order to mitigate the impact of a critical event on family development. There are five levels for family interventions, which are based upon the degree of familial involvement, assuming this would lead to better understanding the individual's problems, and this may also lead to a greater likelihood for solving them. It is also important to know when a family problem may require referral to a next level for intervention. In our country, we need to have adequate services, we have to train professionals with specific abilities in working with families and we also have to reinforce regulations that may facilitate advances in this field.
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Humanos , Atención Primaria de Salud , Medicina Familiar y Comunitaria , Médicos de FamiliaRESUMEN
We present a method for reducing the phase flicker originated by the pulsed modulation of a Liquid Crystal on Silicon (LCoS) Spatial Light Modulator (SLM). It consists in reducing the temperature of the LCoS in a controlled way, in order to increase the viscosity of the liquid crystal. By doing this, we increase the time response of the liquid crystal, and thus reduce the amplitude of phase fluctuations. We evaluate the efficacy of this method quantifying the temporal evolution of phase shift using an experiment that is insensitive to optical polarization fluctuations. Additionally, we determine the effect of the temperature reduction on the effective phase modulation capability of the LCoS. We demonstrate that a reduction of up to 80% of the flicker initial value can be achieved when the LCoS is brought to -8 °C.
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En este artículo se presentan las características de las usuarias y de los servicios de anticoncepción quirúrgica voluntaria, en la Secretaria de Salud, durante el periodo 1981-1984. Los resultados indican que las aceptantes de esta forma de anticoncepción, se caracterizan por una paridad y un promedio de edad elevados, y por un uso de anticonceptivos previo a la intervención relativamente bajo. En cuanto a los servicios, destaca la elevada proporción de cirugías realizadas por médicos y cirujanos generales, el uso poco frecuente de la anestesia local y sedación, la prevalencia de la minilaparotomía y la laparoscopia, como vía de acceso empleada, y el número de complicaciones transoperatorias informadas dentro o abajo de los niveles internacionalmente aceptados